[RFC][PATCH] Postpone print of --help=* option.

[Szabolcs Nagy]

On 01/04/2019 13:11, Martin Liška wrote:
> Hi.
> 
> Last week I was curious which warnings are disabled by default on top
> of -Wall and -Wextra. Thus I used --help=warning and noticed some discrepancy
> in between documentation and output of the --help option.
> 
> I created PR89885 where I explained that OPT__help_ option handling happens
> early. That's why LangEnabledBy are not reflected and similarly target overrides
> don't take place.
> 
> I'm attaching diff for --help=warning for C++ and -Ofast.
> 
> Thoughts?

since this change on arm-* and aarch64-* running RUNTESTFLAGS=help.exp i see

FAIL: compiler driver --help=params --help=optimizers option(s): "maximum number of" present in output
FAIL: compiler driver --help=params option(s): "[^.]$" absent from output: "e"

(indeed previously there were several 'max-*' params
in the output now there are none)

> 
> gcc/ChangeLog:
> 
> 2019-04-01  Martin Liska  <mliska@suse.cz>
> 
> 	* gcc.c (process_command): Add dummy file only
> 	if n_infiles == 0.
> 	* opts-global.c (decode_options): Pass lang_mask.
> 	* opts.c (print_help): New function.
> 	(finish_options): Print --help if help_option_argument
> 	is set.
> 	(common_handle_option): Factor out content of OPT__help_
> 	into print_help.
> 	* opts.h (finish_options): Add new argument.
> ---
>  gcc/gcc.c         |   3 +-
>  gcc/opts-global.c |   2 +-
>  gcc/opts.c        | 267 ++++++++++++++++++++++++----------------------
>  gcc/opts.h        |   3 +-
>  4 files changed, 146 insertions(+), 129 deletions(-)
> 
>